I had the cheap $20 one without the tail light from Road 6 on my old bike. It was good for the price. If I remember correctly, I had to do a little grinding to get it to fit my lower shock mount.
I'm sure you probably want to see a pic of the one with the tail light, but here is mine.
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Nice job on your bike, nice and skinny.
I see that you cut your rails off.
Why don't you move the signals up to the rail using the bolt that's going through that fender.
Or put a light-bar with signals under your fender, there's a lot of room there sine you trimmed it